Salafists protest against Nabil Karoui, the owner of Nessma, a Tunisian private television station, outside a court in Tunis April 19, 2012. Karoui is on trial for 'undermining' sacred Islamic values when his channel broadcast the animated film Persepolis, about Iran's 1979 revolution.

Tunis, Tunisia — When her daughter began wearing the Islamic headscarf three years ago, Amel Bennajeh was so upset that she kicked the teenagers out of the house. They have since reconciled their relationship, but not their views.

Their disagreement over Islamic dress mirrors a larger debate unleashed by revolution here last year that ended decades of dictatorship: Will the new Tunisia be a secular state, an Islamic one, or something in between?

That question underlies a trial hearing today for Nabil Karoui, a TV station owner accused of offending public morals and a recognized religion in October 2011, when his station aired the cartoon film “Persepolis.” The film includes a depiction of God, considered forbidden in Islam.

How Tunisians handle the debate over religion – particularly in the writing of a new constitution now under way – could offer lessons for other Arab countries such as Egypt and Libya, where popular uprisings have empowered Islamists long persecuted by autocratic regimes.

“At a time when we are looking to the Tunisian government to set an example by enshrining full respect for human rights in the country’s new constitution, it is disturbing to see this trial continuing,” said Hassiba Hadj Sahraoui, deputy director of Amnesty International’s Middle East and North Africa program.

“Prosecuting and convicting people on the basis of the peaceful expression of their views, even if some might find them offensive, is totally unacceptable and not what we would expect from the new Tunisia," she said. "It’s reminiscent of the violations of the ousted Ben Ali government and must stop.”

The sharia debate

Today in Tunisia, the moderate Islamist Ennahda party leads a coalition government with two secularist parties and dominates a national assembly that is tasked with writing the new constitution.

Debate has focused on whether that constitution should invoke the Islamic sharia, or “way” – roughly, the commandments and moral sense of the Quran.

Last month thousands of mainly conservative salafi Muslims marched in Tunis to demand sharia and denounce, in the words of one placard, “secularist dogs.”

The next day, Ennahda pledged to keep the first article of the current constitution, which cites Islam as Tunisia’s religion without referring to sharia. "Tunisia is a free, independent and sovereign state. Its religion is Islam, its language is Arabic and its type of government is the Republic," reads a translation provided by the University of Richmond in Virginia.

Secularist parties have welcomed the move.

“We’re in a transitional phase,” says Noureddine Arbaoui, a member of Ennahda’s executive bureau. “Tunisians must join together and make compromises for democratic transition to succeed.”

“We in Ennahda don’t want a religious state, but nor is our state secular,” he says. “We feel that the first article of the constitution is enough to meet people’s desire that Islam play a leading role in Tunisian life.”

However, the article invites interpretation, says Slim Laghmani, a law professor at Carthage University, near Tunis. He says that former presidents Habib Bourguiba and Zine El Abidine Ben Ali used it to justify a half-century of aggressive secularism.

Mr. Ben Ali, who ruled from 1987 until his ouster last year, outlawed Ennahda and jailed thousands of conservative Muslims after the party scored well in 1989 elections.

Mr. Bourguiba, his predecessor, considered Islam a barrier to building a modern state. During three decades in power he banned the headscarf and polygamy, expanded women’s rights, and imprisoned Islamists.

Why a mother worries about her headscarf-wearing daughter

For Mrs. Bennajeh, then growing up, Bourguiba's brand of modernity was a welcome contrast to the endless "no"s of her conservative mother.

“That I could go out of the house alone, that I could go to the cinema – these things that Bourguiba supported, my mother considered shameful,” she says, now facing the opposite battle with her own daughter.

In 2009, Ms. Mkaddem’s interest in the Israeli-Palestinian conflict led her to Islamic piety.

Told to leave home by her mother after donning the Islamic headscarf, Mkaddem stayed for a month with an uncle before returning home and reconciling. Later, police near the college where she studies English language and literature forced her to sign a promise to remove her headscarf.

“It reinforced the way I felt about religion and politics,” she says. “I was sure we were in an evil system.”

Bennajeh sees danger not in secular policies, but in conservative Islam, which she fears could one day threaten her daughter’s freedoms.

“Those who want sharia think women aren’t capable,” she says. “There are men in Tunis who want to shut women in the home.”

“But we’re not asking for sharia, just inspiration by sharia,” protests Mkaddem, who argues that Islam protects women’s dignity.

Any use of sharia as a basis for civil law is complex, says Slim Laghmani, a law professor at Carthage University, near Tunis. Sharia must first be distilled by scholars into regulations called fiqh.

And even once Tunisia's new constitution is written, elected lawmakers will have considerable influence over how it is applied.

“A text is meaningless until it’s interpreted,” says Prof. Laghmani. “He who can impose his interpretation will give the text meaning.”

Elections expected for next year that will shape the new government could thus do as much as Tunisia's constitution to determine the country's future, he says.

Please pray more – and turn down that Metallica

Those eligible to vote include not only young people like Mkaddem, but others like recent university graduate Aymen Ben Abderrahmen.

While Mkaddem thinks the state should move closer to religion, Mr. Ben Abderrahmen wants it to go the other way.

“We can have a secular state in practice without making people fear that their religion is under attack,” he says. At the same time, “restrictions on religion should be abolished.”

Last month a judge sentenced two men to seven-year jail terms for publishing writings and cartoons critical of Islam. The judge cited laws that outlawed offense to public morals under former President Ben Ali.

Ben Abderrahmen was part of a large demonstration outside the Interior ministry on Jan. 14, 2011, that was crucial in prompting Ben Ali to flee the country that night.

As Ben Abderrahmen watched police beat protesters amid billowing tear-gas, his 20-year-old sister, Ons, sat at home and wished she was with him.

“When Ben Ali left I thought, ‘At last! I can live my religion without anyone bothering me’,” says Ons, who began wearing the Islamic headscarf two years ago and supports a state based on Islam.

But whereas Mkaddam met resistance at home for the same decision, Ms. Ben Abderrahmen has found acceptance.

When Ms. Ben Abderrahmen began wearing Islamic clothes, her brother helped buy them. Sometimes she asks him to pray more – and to turn down his Metallica in the Tunis house they share with their parents and a younger brother.

“And then he jokes that he’s going to hell and will see Metallica there live in concert,” she says with a smile.

Aymen Ben Abderrahmen is planning to launch an online forum to discuss the new constitution. His sister, a computer science student, plans to help.

“This debate will never finish,” he says. “I can still see people on Facebook and on the street talking about it.”